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</style></head><body><table border="0" cellpadding="0" cellspacing="0" width="100%"><tr /><td align="left" valign="top" width="32"><img align="left" border="0" height="32" src="images/rb-logo.png" width="32" /></td><td width="1">&#160;&#160;</td><td class="postheader" valign="center"><a href="../pyqt4ref.html"><font color="#004faf">Home</font></a>&#160;&#183; <a href="classes.html"><font color="#004faf">All Classes</font></a>&#160;&#183; <a href="modules.html"><font color="#004faf">Modules</font></a></td></table><h1 align="center">QExtensionFactory Class Reference<br /><sup><sup>[<a href="qtdesigner.html">QtDesigner</a> module]</sup></sup></h1><p>The QExtensionFactory class allows you to create a factory that is able to make instances of custom extensions in Qt Designer. <a href="#details">More...</a></p>
<p>Inherits <a href="qobject.html">QObject</a> and <a href="qabstractextensionfactory.html">QAbstractExtensionFactory</a>.</p><h3>Methods</h3><ul><li><div class="fn" /><b><a href="qextensionfactory.html#QExtensionFactory">__init__</a></b> (<i>self</i>, QExtensionManager&#160;<i>parent</i>&#160;=&#160;None)</li><li><div class="fn" />QObject <b><a href="qextensionfactory.html#createExtension">createExtension</a></b> (<i>self</i>, QObject, QString, QObject)</li><li><div class="fn" />QObject <b><a href="qextensionfactory.html#extension">extension</a></b> (<i>self</i>, QObject, QString)</li><li><div class="fn" />QExtensionManager <b><a href="qextensionfactory.html#extensionManager">extensionManager</a></b> (<i>self</i>)</li></ul><a name="details" /><hr /><h2>Detailed Description</h2><p>The QExtensionFactory class allows you to create a factory that is able to make instances of custom extensions in Qt Designer.</p>
<p>In <i>Qt Designer</i> the extensions are not created until they are required. For that reason, when implementing a custom extension, you must also create a QExtensionFactory, i.e. a class that is able to make an instance of your extension, and register it using <i>Qt Designer</i>'s <a href="qextensionmanager.html">extension manager</a>.</p>
<p>The <a href="qextensionmanager.html">QExtensionManager</a> class provides extension management facilities for Qt Designer. When an extension is required, Qt Designer's <a href="qextensionmanager.html">extension manager</a> will run through all its registered factories calling <a href="qextensionfactory.html#createExtension">QExtensionFactory.createExtension</a>() for each until the first one that is able to create a requested extension for the selected object, is found. This factory will then make an instance of the extension.</p>
<p>There are four available types of extensions in Qt Designer: <a href="qdesignercontainerextension.html">QDesignerContainerExtension</a> , <a href="qdesignermembersheetextension.html">QDesignerMemberSheetExtension</a>, <a href="qdesignerpropertysheetextension.html">QDesignerPropertySheetExtension</a> and <a href="qdesignertaskmenuextension.html">QDesignerTaskMenuExtension</a>. Qt Designer's behavior is the same whether the requested extension is associated with a multi page container, a member sheet, a property sheet or a task menu.</p>
<p>You can either create a new QExtensionFactory and reimplement the <a href="qextensionfactory.html#createExtension">QExtensionFactory.createExtension</a>() function. For example:</p>
<pre>         QObject *ANewExtensionFactory.createExtension(QObject *object,
                 const QString &amp;iid, QObject *parent) const
         {
             if (iid != Q_TYPEID(QDesignerContainerExtension))
                 return 0;

             if (MyCustomWidget *widget = qobject_cast&lt;MyCustomWidget*&gt;
                    (object))
                 return new MyContainerExtension(widget, parent);

             return 0;
         }</pre>
<p>Or you can use an existing factory, expanding the <a href="qextensionfactory.html#createExtension">QExtensionFactory.createExtension</a>() function to make the factory able to create your extension as well. For example:</p>
<pre>         QObject *AGeneralExtensionFactory.createExtension(QObject *object,
                 const QString &amp;iid, QObject *parent) const
         {
             MyCustomWidget *widget = qobject_cast&lt;MyCustomWidget*&gt;(object);

             if (widget &amp;&amp; (iid == Q_TYPEID(QDesignerTaskMenuExtension))) {
                 return new MyTaskMenuExtension(widget, parent);

             } else if (widget &amp;&amp; (iid == Q_TYPEID(QDesignerContainerExtension))) {
                 return new MyContainerExtension(widget, parent);

             } else {
                 return 0;
             }
         }</pre>
<p>For a complete example using the QExtensionFactory class, see the <a href="designer-taskmenuextension.html">Task Menu Extension example</a>. The example shows how to create a custom widget plugin for Qt Designer, and how to to use the <a href="qdesignertaskmenuextension.html">QDesignerTaskMenuExtension</a> class to add custom items to Qt Designer's task menu.</p>
<p>See also <a href="qextensionmanager.html">QExtensionManager</a> and <a href="qabstractextensionfactory.html">QAbstractExtensionFactory</a>.</p>
<hr /><h2>Method Documentation</h2><h3 class="fn"><a name="QExtensionFactory" />QExtensionFactory.__init__ (<i>self</i>, <a href="qextensionmanager.html">QExtensionManager</a>&#160;<i>parent</i>&#160;=&#160;None)</h3><p>The <i>parent</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs an extension factory with the given <i>parent</i>.</p>
<a name="//apple_ref/cpp/instm/QExtensionFactory/createExtension" />
<h3 class="fn"><a name="createExtension" /><a href="qobject.html">QObject</a> QExtensionFactory.createExtension (<i>self</i>, <a href="qobject.html">QObject</a>, QString, <a href="qobject.html">QObject</a>)</h3><p>The <i>QObject</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Creates an extension specified by <i>iid</i> for the given <i>object</i>. The extension object is created as a child of the specified <i>parent</i>.</p>
<p>See also <a href="qextensionfactory.html#extension">extension</a>().</p>
<a name="//apple_ref/cpp/instm/QExtensionFactory/extension" />
<h3 class="fn"><a name="extension" /><a href="qobject.html">QObject</a> QExtensionFactory.extension (<i>self</i>, <a href="qobject.html">QObject</a>, QString)</h3><p>Reimplemented from <a href="qabstractextensionfactory.html#extension">QAbstractExtensionFactory.extension</a>().</p>
<p>Returns the extension specified by <i>iid</i> for the given <i>object</i>.</p>
<p>See also <a href="qextensionfactory.html#createExtension">createExtension</a>().</p>
<a name="//apple_ref/cpp/instm/QExtensionFactory/extensionManager" />
<h3 class="fn"><a name="extensionManager" /><a href="qextensionmanager.html">QExtensionManager</a> QExtensionFactory.extensionManager (<i>self</i>)</h3><p>Returns the extension manager for the extension factory.</p>
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